Zigzag stitching machine



June 23, 1936. W. BLTER 2,045,340

ZIGZAG STITCHING MACHINE Filed Nov. 22, 1934 4 Sheets-Sheet 1 June 23, 1936. W. BLTER ZIGZAG STITGHING MACHINE June 23, 1936. w. BLTER 2,045,340

ZIGZAG STITCHING MACHINE Filed Nov. 22, 1934 4 Sheets-Sheet 3 f AA M- Q June 23, 1936. W BLTER ZIGZAG STITCHING MACHINE Filed Nov. 22. 1954 4 Sheets-Sheet 4 Patented June 23, 1936 UNITED STATES zIczAG srl'rcmNc MACHINE Wilhelm Blter. Bielefeld, Germany, assigner to Anker-Werke, A. G., Bielefeld, Germany Application November 22, 1934, Serial No. 754,301 In Germany November 23, 1933 23 Claims.

The 'instant invention relates to sewing machines embodying a zigzag stitch forming mecha.- nism. 'I'he object of the invention is to provide such a sewing machine for household purposes which is particularly economical to produce and which however operates simply and with certainty.

It is one of the features of the invention to adapt to such a machine a shuttle having an oscillating movement of the type known as an oscillating shuttle, which is cheaper than the rotary hook type.

It has been proposed previously to employ such a shuttle in zigzag stitch forming machines so that the shuttle carrier is arranged in the longitudinal axis of the machine, so that the needle bar swings in the direction of movement of the shuttle point. 'I'his arrangement has the disadvantage that the transmission of the oscillating driving movement to the shuttle involves too costly and complicated transmission elements. and aside from this, that the extraction of the shuttle from its housing is inconvenient.

In accordance with the instant invention, the use of an oscillating shuttle for such a machine is attained by arranging the shuttle housing so that it executes an oscillating movement coincidentally with the movement of the-needle bar, although in the usual manner they are arranged transversely. Another feature of the invention resides in the regulation of the lateral swinging of the shuttle housing from the same setting elements which adjust the lateral swing of the needle bar.

In accordance with the particularly advantageous construction of the illustrative machine described herein, it is possible to attain in a household zigzag stitch-forming machine, a controllable setting for the direction of the throw of the needle from its mid-position, as well as for the extent of the lateral throw of the needle. This is at' tained by an arrangement, for the regulation of the lateral throw of the needle-bar by means of a grooved block eccentrically mounted in a rotat` able member. As a result of this arrangement, the extent of the lateral throw may be controlled by the setting of the groove in known manner, while as a new result, the direction of the throw of the needle from its mid-position is regulated by a special setting lever.

Two diiferent embodiments of the invention are illustrated, namely; one embodiment in which the shuttle housing and thereby the point of the shuttle describes a downwardly directed open arc, and another embodiment in which the shuttle housing and thereby the point thereof describes an upwardly directed open arc.

In accordance with the second embodiment, while retaining the main feature of thev invention concerning the oscillating movement of the 5 shuttle housing, the shuttle housing is itself swingingly suspended, so that the point of the movable shuttle in the housing describes an upwardly dlrected open arc, while the driver of the shuttle does not partake of this swinging movement, re- 10 ceiving only an axial shifting. In combination with the new arrangement, the forked connecting rod for transmitting the oscillating movement to the needle frame is arranged above the top shaft of the sewing machine arm.

. By this arrangement. the advantagesattained over the ilrst embodiment of the invention and furthermore over other known zigzag stitch forining machines with horizontally shiftable shuttle housings, is that the danger of the skipping of 20 stitches is eliminated. This advantage arises from the fact that the shuttle point here is lifted against the loop so that the formation of the loops in the end positions is rendered easier.

By means of the displacement of the forked 25 connecting rod for the drive of the needlebar above the top shaft, the opening under the horlzontal bracket-arm is not constricted at the curve merging into the vertical portion of the machine arm.

It is known in zigzag stitch forming machines to displace the starting point of the lateral throw of the needle.

In accordance with the instant invention, the displacement of the starting position of the lateral swing of the needle is obtained by shifting laterally the pivot point of the grooved block for the stitch regulator, by means of an eccentric, through' half the extent of the maximum width of the stitch. Thereby the advantage is attained that 40 a slot of smaller extent in the stitching plate suffices for all cases.

In accordance with the invention, a plate is inserted in the sewing machine arm in which, according to the arrangement in the rst embodii ment, is-provided a rotatable member. A bolt is eccentrically arranged in this rotatable member which transmits the adjusting movement to the groove, in known manner, for the purpose of regulating the size of the stitch. Since the setting 60 lever for determining the direction of the throw' of the needle-bar is connected with the rotatable member and since the setting lever for regulating the width of stitch is mounted on the eccentrically disposed bolt, the setting device may be inserted in the sewing machine arm as a complete unit. In accordance with the invention, a protecting cap is mounted over the setting lever which is screwed upon the plate carrying the setting lever. The opening for the setting lever in this cap is provided at the same time with a. setting device for the setting lever formed according to the invention from a resilient steel yoke for regulating the width of the stitch.

The first embodiment of the invention is illustrated in Figs. 1-3, the second embodiment in Figs. 4-7, while Figs. 8-11 show a particularly advantageous form of setting means which may be applied to the sewing machine arm.

In the drawings:

Figure 1 shows schematically a front View of the rst embodiment of the invention,

Figure 2 is a plan View of a part of Figure 1, as well as Figure 4,

Figure 3 is a sectional view through the ma.- chine at the regulating mechanism, showing the elements thereof in accordance with the first embodiment of the invention,

Figure 4 is a view corresponding to Figure 1 of the second embodiment of the invention,

Figure 5 is a sectional view corresponding to Figure 3 of the second embodiment of the invention,

Figure 6 is a front view of the head of the' forked rod shown in Figures 4 and 5.

Figure 7 is a diagram showing the control of the width of the stitch according to the embodiment shown in Figures 4-6,

Figure 8 is a front view of the arrangement of the setting means,

Figure 9 is a sectional view along line 9--9y tion illustrated in Figures 1-3, the frame I carrying the needle bar is mounted to pivot about a point 2 and is capable of assuming the designated end positions from the mid-position shown schematically in Figure 2. The lateral swinging of the needle frame is effected by means of forked lever 3, the fork 4 of which embraces an eccentric 8 mounted upon shaft 5. The eccentric 6 is driven in known manner from the top shaft of the sewing machine. The forked rod 3 carries a guide block 2| which is guided in known manner in a guide groove 'I of the grooved block 8. The block 8 is adjustable in known manner by means of an adjusting lever, 9 whereby the extent of the lateral swinging movement of the needle is regulated.

In accordance with the invention, the grooved guide block 8 is eccentrically mounted in a bush ID which is rotatably arranged in the machine arm II. l'Ihe bush I0 is connected with a lever I2 which preferably has three positions.

A pin I3 is connected with the block 2|, which is movable in guide groove l, which pin extends through a bore in the forked end 4 of connecting rod 3. This pin is furthermore embraced by a longitudinal slot |4 of double armed lever I6 pivoted upon pin I5. The lower arm of lever I6 is jointedly connected to one end of draft rod I'I, the other end of which engages the shuttle housing I8. The shuttle housing I8 is pivotally mounted upon two pins I9.

The apparatus described above operates in the following manner: l

By means of the setting lever I2 and the rotation of the bush l0 thereby, the pivotal'point of the grooved block 8 may be shifted so that the needle frame I and, together therewith, the shuttle housing I8 execute either an oscillating movement on both sides of their mid-positions or these elements execute an oscillating movement on one or the other side of their mid-positions. By means of the setting lever 9, the extent of the lateral throw of these elements from their midpositions may be regulated in known manner.

In the embodiment shown in Figures 4-7, the needle frame I carrying the needle bar is mounted vto pivot about a point 2 and is capable of assuming the end positions from the indicated mid-position shown in Figure 2. 'Ihe lateral swinging movements of the needle frame I are generated by means of the forked rod 3, the fork 4 of which embraces an eccentric 6 mounted upon shaft 5. The eccentric 6 is driven in known manner from the top shaft of the sewing machine. The forked rod 3 carries in a projection of its fork 4, a block 2| whichl is guided in a groove 'I of the guide block 8 in known manner. The block 8 is adjustable, in known manner, through its bolt 22 by means of setting lever 9, whereby the extent of the lateral swinging movement ofthe needle may be regulated. The bolt 22 connected with the block 8 is'mounted eccentrically in bush |0, which in turn is rotatably disposed in machine arm I I. The bush .I0 is rigidly connected with lever I2 whereby the former may be adjusted by the latter in different positions. Three settings for the lever I2 are possible, Whereupon from time to time use is made of the midposition setting and either one of the end settings. A pin I3 is connected with the block 2| movable in guide groove 1, which pin extends through a bore in fork 4 of rod 3 (Figs. 5 and 6). A longitudinal slot I4 (Fig. 4) of a double-armed lever I6 embraces the pin I3. The double-armed lever I6 is pivoted upon pin I5 and isfurthermore jointedly connected with another double-armed lever 23 which is pivoted upon pin 24 and which is jointedly connected with one end of draft rod I'I. The draft rod Il engages with a transverse yoke 25 of a sleeve 26, which is axially shiftable in a bearing 21 cast on the machine plate 28, and which is connected with the actuator 29 of the shuttle so that the latter partakes of the axial shifting movement of the sleeve. A drive shaft 3| is mounted in the bore of the sleeve 26 which is coupled by means of a coupling 32 with a drive shaft 33 for oscillating movement. The transverse yoke 25 is jointedly connected at its lower end with a link 34 rigidly connected with the shuttle housing. The link 34 is furthermore guided by means of a guiding projection 36 on the bearing 21. 'Ihe shuttle housing 35 is swingingly suspended by means of two hanging arms 36 on the underside of the sewing machine plate.

The mode of operation of the apparatus described above may be explained by the following:

The pivot point of thc bush I0 in the machine arm |I is so chosen in accordance with the invention that the rotation of this bush shifts the pivot point 22 of the guide block 8 along a line 70 point in Figure 7 corresponds to the forked 75 connecting rod I. It is apparent from Figure 'I that according to the new kinematic relation Aof the parts the starting point of the lateral throw or the needle bar is displaced to the left -by means of lever I2 to an extent equivalent to so that instead of the middle stitch diagram in Figure 'I which is common to the embodiment shown in Figures i-3 as well as to that shown in Figures 4 6, the diagram immediately below the common diagram or the second one from the bottom in Figure 7 is obtained. By the regulation of the width of the stitch by means of lever 9, the lateral swing of the needle bar may be diminished to zero so that a straight closing seam results. Instead of a displacement of the pivot point of the grooved block to the left, it is possible to displace it to the right with reference to its mld-position, in accordance with the upper control triangle, in which case instead oi! the lower withdrawn setting for the lever 9, the upper withdrawn position is used, or else the bush I0 is itself shiftably arranged in the machine arm II. In contrast to the arrangement shown in Figures 1-3 in which the needle may be swung either to one side or to the other side, a shortening of the slot in the stitching plate, which may be used for all cases, is attained hereby.

'Ihe insertion of the adjusting mechanism in the sewing machine arm may be effected in the manner illustrated in Figures 8-11, as described in detail `below:

The same parts which are shown in the embodiments described above are designated by like reference characters.l Therefore, the rotatable body I 0 in the novel arrangement disclosed in these figures is illustrated as. rotatably mounted in a plate 3|', which is fastened to the sewing machine arm by screws 32. A bolt 33' is rotatably mounted within the rotatable body III and the guide block 8 is rigidly connected with the former. The setting lever 9 is xed upon the front end of bolt 33 and .is built in the form of a resilient steel yoke which in known manner eects an adjustment of the width ofthe zigzag stitch by rotation of the guide block 8. The lever 9 is maintained in its adjusted position by means of a cap or supplementary plate 35 which is screwed into the plate 3i' with screws 34 leaving an opening 36" for the lever 9, which opening is provided with a toothed edge formed by small notches 31. The nose 38 of lever 9 resiliently engages these notches (Figs. 10 and 11). A scale is provided on the outside of plate 35' over the toothed edge, and a projection bent from the lever 9 cooperates therewithl above and illustrated in Figures 8-11 is not limited in its application to a stitch forming mechanism embodying an oscillating shuttle housing,

' the mechanism for transmitting the oscillating arrangement shown in the embodiment in Figures 1-3, Figures 9 and 10 show a shaft 5 mounted in the sewing machine arm I I on which is xed an'eccentric l which is embraced bythe iork 4 of the forked connecting rod and which furthermore is driven in known manner from the upper shaft of the machine. This fork 4 has, corresponding to the embodiments described above. a projection 39 in which is riveted a pin I3 which engages in the grooved block 8.

Having described my invention, what I claim is:

1. In a sewing machine, particularly for household use, a zigzag stitch forming mechanism comprising a shuttle housing mounted for oscillatory movement about a horizontal axis perpendicular to the longitudinal axis ot the machine, a shuttle in said housing, means to impart an oscillatory movement to said shuttle, a needle bar, a rod for oscillating said needle bar transversely oi' its axis, and driving means for actuating said rod and for imparting an oscillating movement to said housing concomitantly with the movement of said needle bar.

2. In a sewing machine, particularly for household use, a zigzag stitch forming mechanism comprising a shuttle housing mounted for oscillatory movement about a horizontal axis perpendicular` to the longitudinal axis of the machine, a shuttle in said housing. means to impart an oscillatory movement to said shuttle, a needle bar, an actuating rod for laterally oscillating said needle bar, driving means for actuating said rod and for imparting an oscillating movement to said housing concomitantly with the movement of said needle bar, and common regulating means for controlling the oscillating movement of said needle bar and said shuttle housing.

3. The combination claimed in claim 2 wherein said common regulating means comprises a rotatable member, and a grooved block mounted eccentrically in said member.

4. The combination claimed in claim 2 whereinsaid common regulating means comprises a rotatable member, a regulating lever connected with said member for adjusting the field of the oscillating movement of said needle bar, a

grooved block mounted eccentrically in said member, and a regulating lever for adjusting the setting of said block for controlling the extent of oscillating movement of said needle bar.

5. The combination claimed in claim 2 wherein said commion regulating means comprises a rotatable member disposed in the sewing machine arm, a regulating lever connected with said member for adjusting the eld of the oscillating movement of said needle bar, a bore disposed eccentrically in said member, a bolt in said bore, a grooved block at the end of said bolt, and a second regulating lever connected with said bolt for adjusting the setting of said block for controlling the extent of oscillating movement of said needle bar.

6. In a sewing machine, particularly for household use. a zigzag stitch forming mechanism comprising a shuttle housing, a needle bar, an actuating rod for laterally oscillating said needle bar, driving means for actuating said rod and for imparting an oscillating movement to said housing concomitantly with the movement of said needle bar, and common regulating means for controlling the oscillating movement of said needle bar and said shuttle housing, said regulating means comprising a rotatable member disposed in the sewing machine arm, a regulating lever connected with said member for adjusting the field of the oscillating movement of said needle bar, a bore disposed eccentrlcally in said member, a bolt in said bore. a grooved block at the end of said bolt, and a second regulating lever connected with said bolt for adjusting the setting of said block for controlling the extent of oscillating movement of said needle bar, a lug on said actuating rod engaging the groove in said grooved block, a pin connected with said lug, and a double armed lever having one arm thereof connected with said shuttle housing and the other arm terminating in a longitudinal slot embracing said pin.

7. In a sewing machine, particularly for household use, a zigzag stitch forming mechanism comprising a shuttle housing, a needle bar, an actuating rod for laterally oscillating said needle bar, driving means for actuating said rod and for imparting an oscillating movement to said housing concomitantly with the movement of said needle bar, and common regulating means for controlling the oscillating movement of said needle bar and said shuttle housing, said regulating means comprising a rotatable member disposed n the sewing machine arm, a regulating lever connected with said member for adjusting the' iield of the oscillating movement of said needle bar, a bore disposed eccentrically in said 'memben a bolt in said bore, a grooved block at the end of said bolt, and a second regulating lever connected with said bolt for adjusting the setting of said block for controlling the extent of oscillating movement of said needle bar, an extension on said actuating rod at the end thereof opposite the needle bar, a lug on said extension engaging the groove in said grooved block, a pin connected with said lug, and a double-armed lever having one arm thereof connected with said shuttle housing and the other arm terminating in a longitudinal slot embracing said pin.

8. In a sewing machine, particularly for household use, a zigzag stitch forming mechanism comprising a needle bar, a rod for oscillating said needle bar transversely of its axis, a plate below said needle bar, a pair of arms swingingly suspended from the underside of said plate, a shuttle housing carried by said arms, a shuttle in said housing, the point of said shuttle describing an upwardly open arc as said housing swings, and driving means for actuating said rod,

and connections between said driving means and said shuttle housing for imparting an oscillating movement to the latter concomitantly with the movement of said needle bar.

9. In a sewingmachine embodying an arm, particularly for household use, a zigzag stitch forming mechanism comprising a shuttle housing, a needle bar, an actuating rod for laterally oscillating said needle bar, driving means for actuating said rod, connections between said driving means and said shuttle housing for imparting an oscillating movement to said housing concomitantly with the movement of said needle bar, and common regulating means for controlling the oscillating movement of said needle bar and said shuttle housing comprising a rotatable member, a plate for retaining said member, an opening in said sewing machine arm for` receiving said plate, a regulating lever connected with said member for adjusting the eld of the oscillating movement of said needle bar, a bore disposed eccentrically in said member, a bolt in said bore, a grooved block at the end of said bolt,

and a second regulating lever connected with said bolt for adjusting the setting of said block for controlling the extent of oscillating movement of said needle bar.

10. 'I'he combination claimed in claim 9 wherel in a supplementary plate is superposed over said member retaining plate and over said regulating levers, and means on said supplementary plate for holding at least one of said regulating levers A in its adjusted position.

11. The combination claimed in claim 9 wherein one of said regulating levers is formed resiliently. a supplementary plate superposed over said member retaining plate and over said regulating levers, and a toothed portion on said supplementary plate cooperating with said resilient lever to maintain said lever in its adjusted posi- 12. The combination claimed in claim 9 wherein one of said regulating levers is formed resiliently, a supplementary plate superposed over said member retaining plate and over said regulating lcvers,'a toothed portion on said supplementary plate cooperating with said resilient lever to maintain said lever in its adjusted position, a scale on the outside of said supplementary plate adjacent said toothed portion, and a projection bent from said resilient regulating lever in proximity `to said scale.

13. In a sewing machine, particularly for household use, a zigzag stitch forming mechanism comprising a needle bar, a rod for oscillating said needle bar transversely of its axis, a shuttle housing, va shuttle in said housing, said shuttle housing being swingingly suspended below said needle bar, whereby the point of said shuttle moves along an upwardly open arc as said housing swings, driving means for actuating said rod, and connections between said driving means and said shuttle housing for swinging the latter concomitantly with the movement of said needle bar.

14. In a sewing machine, particularly for household use, a zigzag stitch forming mechanism comprising a needle bar, a rod for oscillating said needle bar transversely of its axis, a shuttle housing, a shuttle in said housing, said shuttle housing being swingingly suspended below said needle bar, whereby the point of said shuttle moves along an upwardly open arc as said housing swings, an axially movable actuator for oscillating said shuttle in said housing, driving means for actuating said rod, and connections between said driving means and said shuttle housing for swinging the latter, said connections having means engaging said shuttle actuator to shift the same axially.

15. In a sewing machine, particularly for household use, a zigzag stitch forming mechanism comprising a needle bar, a rod for oscillating said needle bar transversely of its axis, a4

shuttle housing, a shuttle in said housing, said shuttle housing being swingingly suspended below said needle bar, whereby the point of said shuttle moves along an upwardly open arc as said housing swings, a sleeve movable axially substantially in the direction in which said housing swings, a drive shaft mounted to oscillate in said sleeve, an actuator en said drive shaft for oscillating said shuttle in said housing, said shaft and actuator being movable axially with said sleeve, driving means for actuating said rod, and connections leading from said driving means to said sleeve and to said shuttle housing for imparting axial movements to the former and swinging movements to the latter, concomitantly with the movement of said needle bar.

16. In a sewing machine, particularly for household use, a zigzag stitch forming mechanism comprising a needle bar, a rod for oscillating said needle bar transversely of its axis, a shuttle housing, a shuttle in said housing, said shuttle housing being swingingly suspended below said needle bar, whereby the point of said shuttle moves along an upwardly open arc as said housing swings, a sleeve movable axially substantially in the direction in which said housing swings, a drive shaft mounted to oscillate in said sleeve, an actuator on said drive shaft for oscillating said shuttle in said housing, said shaft and actuator being movable axially with said sleeve, a transverse yoke connected to said sleeve at the end thereof opposite said actuator, eccentric driving means for actuating said rod, connections between said eccentric and said yoke for imparting axial movements to said sleeve, and means for'transmitting movements to said shuttle housing concomitantly with the movement of said needle bar.

17. A sewing machine as described in claim 16, wherein said means for transmitting movements to said shuttle housing comprises a link extending between the lower end of said transverse yoke and said shuttle housing.

18. A sewing machine as described in claim 16, wherein said means for transmitting movements to said shuttle housing comprises a link extending between the lower end of said transverse yoke and said shuttle housing, said sleeve being mounted in a bearing, said link being guided in a groove in said bearing.

19. In a zigzag stitch sewing machine, a horizontal bracket, a main driving shaft in said bracket, a needle bar mounted on said bracket so as to oscillate transversely to its axis, a rod disposed above said main driving shaft in said bracket and connected to said needle bar for oscillating the same, an eccentric for imparting up and down movements to the end of said rod remote from said needle bar, said remote end oi' said rod having a downward projection bearing a guide follower, a guide lfor said follower mounted on said bracket, a swinging shuttle housing, and 5 connections between the downward projection of saidrod and said shuttle housing, said guide being adapted to impart axial motions to said rod to swing said needle bar and said shuttle housing concomitantly. l0

20. A sewing machine as described in claim 19, wherein said connectionsl between said downward projection and said shuttle housing comprise two llrst class levers jointed together, the, remote end of one lever being connected to said 15 shuttle housing, the remote end of thefother lever being provided with a slot, said downwardpro- Jection bearing a bolt extending through said slot.

`21. A sewing machine as described in claim 15, 20 wherein said drive shaft is divided into two parts connected by a coupling permitting relative axial movement of said parts, one of said parts extending through said sleeve and the other being connected to the main driveof the machine. 25

22. A sewing machine as described in ,claim 13, wherein said driving means comprises an eccentric for swinging the end of said rod remote from said needle bar up and down, a pivotally mounted guide block having an inclined guide groove, a follower on said rod travelling in said groove to reciprocate said rod longitudinally, and means for adjusting the position of the pivot of said guide block along an inclined line.

23. A sewing machine as described in claim 2, wherein said common regulating means comprises a rotatable member, a grooved block mounted eccentrically in said member, and a plate on which said rotatable member is mount- WmHELM BLTER. 

